It is holiday season again and the dreaded unwanted, unhealthy, and un-returnable gift of weight gain is back in the news and the topic of numerous articles (including this one). It is not unusual to find weight gain on surveys focusing in one way or another on the holidays. For example, in Consumer Reports’ survey on what Americans dread most about the holidays, holiday weight gain (37%) tied for second-place with getting into debt (37%) (Consumer Reports, 2011).

Gaining weight is on the minds of many Americans and for good reason. According to the National Center for Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), the National Health and Nutrition Examination Survey (NHANES) revealed that in 2007-2008, when adjusting for age, an estimated 34.2% of American adults 20 years of age and older were overweight, while 33.8% were obese (Ogden & Carroll, 2010). The overall prevalence estimates for overweightand obesity when combined for adults 20 years of age and older (BMI 25) was a stunning 68.0%(Ogden & Carroll, 2010). Another way to think about the overweight and obesity epidemic is that less than a third of adults (i.e., 31.6%) in the United States are at a healthy weight.

How Much Weight Is Gained During the Holidays?

There are a number of claims made in the literature about how much weight people gain during the holidays. Depending on whom you read or listen to about it, the amount of weight gain from Thanksgiving to New Year’s Day or the week after could range from 1-10 pounds. However, is the amount of holiday weight gain on the high or low end of the claims made about holiday weight gain or otherwise is it as bad as people believe it to be or is it worse? Because of all the conflicting claims there is considerable conceptual confusion about how much weight is actually gained during the holidays.

The December, 2012, issue of Health and Wellness Monthly seeks to separate fact from fiction on the issue of holiday weight gain, one of the biggest holiday dreads. Particular attention will be devoted to the scientific studies related to holiday weight gain and how much weight is actually gained during the holidays.

Scientific Studies on Holiday Weight Gain

My independent review of the literature did not uncover any scientific study with statistically significant results indicating an average ten pound increase in weight during the holidays. However, as it will be revealed below this does not mean that holiday weight gain is not an important health issue. So how much weight is gained during the holidays?

One of the earliest studies on holiday weight gain was in 1985. Rees et al. (1985) found that normal study participants gained 0.9kg, while diabetics gained 0.7 kg, with 64% gaining over 1 kg.[i] There was a non-diabetic woman who gained 4.3 kg, which was more than any of the study participants. Hence, “a highly significant increase in weight occurred in both normal subjects and diabetics during Christmas, which persisted even a month later” (p. 1765). Rees et al. (1985) estimated that there was an average consumption of 6,160 calories over five days covering, before, during and after Christmas.

Seven years later, Andersson and Rossner (1992) conducted a study with obese patients who had lost weight and were participating in a weight-loss maintenance program. They were compared to subjects in a control group. Andersson and Rossner (1992) reported that the control subjects gained 0.4 kg and experienced little deviation in their weight over a 2-3 week period during Christmas holiday, while the obese subjects gained 0.6 kg and differed by more than 16 kg in weight change.

Another seven years later, Reid and Hackett (1999) conducted an experiment similar to the experiment Rees et al. (1985) did. There was two measurement sessions, with the average number of days between the two measurement sessions being 15.5 days. The average amount of weight gain over this period of time was 0.93 kg. Of the 26 subjects in the study, 12 gained more than 1 kg, four subjects gained more than 2 kg, with the maximum amount of weight gained being 4.4 kg. Given the average amount of weight gained in the study, Reid and Hackett (1999) estimated the average increase in energy to be 6500 calories during the Christmas holiday study period.

In “A Prospective Study of Holiday Weight Gain,” Yanovski et al. (2000) reported that “[in] contrast to the common perception that weight increases during the winter holiday season, the measured weight of the vast majority of subjects in [the] study changed little between Thanksgiving and New Year’s Day” (p. 866). Although they believed they had gained as much as four times the weight that they actually did gain, participants in the study experienced a holiday weight gain of 0.37 kg, which would be less than a pound. Less than 10% of the study participants gained 2.3 kg or more and over 50% of all weight measurements following the initial measurement were within 1 kg of the previous measurement (see Yanovski, et al., 2000).

Those in the study who were overweight or obese gained 2.3 kg (5.07lb), which the researchers in the study described as “a major holiday weight gain.” A similar effect was found in a sample of 91 3rd, 4th and 5th grade mid-western public elementary school children in that the overweight and obese children gained more weight during the holiday period examined compared to their normal weight peers (Branscum et al., 2010).

Furthermore, although subjects in the prospective study gained on average less than a pound during the winter holiday period, the weight gained was not lost over the remainder of the year. In fact, not only had they not lost the holiday weight they gained, the subjects ended the year weighing 0.62kg (.62 kilograms = 1.36686603 pounds), all of which suggests that most of the weight gained during the year occurred during the six-week holiday period.

In short, the weight gained during the holidays became the unwanted, un-returnable gift that kept on giving and could be such a gift each holiday season, unless there is a successful effort to lose the holiday weight and post-holiday weight. This prospective study of holiday weight gain study suggests that failing to lose the weight gained each holiday season and post-holiday period could result in better than 10 pounds of weight gained over 10 years.

In a study examining “The Effect of the Thanksgiving Holiday on Weight Gain,” college students enrolled at the University of Oklahoma experienced an increase of 0.5 kg in body weight just during the Thanksgiving holiday. The researchers in the study commented that “although this may seem like a trivial amount of weight, considering the short time frame, this is troublesome since previous research suggests weight gained during holiday periods is retained” (Hull et al., 2006, p.4). Furthermore, similar to the findings of Yanovski, et al. (2000) and Branscum et al., 2010, those study participants who were overweight or obese gained more weight (1.0 kg) during Thanksgiving than those who were not overweight or obese. Graduate students also tended to gain more weight (0.8 kg) than undergraduate students.

In another study involving college students, Hull et al., (2006) it was found that although Average body weight remained relatively unchanged from pre-Thanksgiving to post-New Year’s, there was a statistically significant increase in the percent of body fat and fat mass.

Finally, in a study exploring the question of whether or not holiday weight gain is a fact or fiction, Roberts and Mayer (2000) examined the amount of holiday weight gain in adults and its contribution to annual weight gain. They found that weight gain during the six-week period from Thanksgiving to New Year study participants had an average increase in weight of only 0.37 kg. However, similar to the other studies discussed above, individuals who were overweight or obese (14% of them) gained more weight (>2.3 kg – 5lb) than those who were not overweight or obese. Furthermore, when considering the entire population, the weight gained during the six-week holiday period accounted for 51% of annual weight gain (see Roberts & Mayer, 2000). Roberts & Mayer (2000) remarked that the results of their study suggest that holiday weight gain could be an important factor in contributing to the increase in the prevalence of obesity.

Conclusion

A review of the literature reveals that holiday weight gain is in one sense not as bad as some would make it out to be in terms of the total amount of weight gained during the holiday period from Thanksgiving to New Year. In two of the studies reviewed (i.e., Roberts & Mayer, 2000; Yanovski et al., 2000), study participants gained less than a pound of weight (i.e., 0.37kg) during the holiday season. In the study focusing on the amount of weight gain during Thanksgiving, there was an increase of 0.5 kg in body weight, a relative significant amount of increase compared to 0.37 kg in that the increase in weight occurred just during Thanksgiving.

A Little Means A Lot But In A Bay Way

Nevertheless, the amount of weight gain in the three studies reviewed is far from a 10 pound increase in weight often claimed in the literature. However, the data show that it is not necessarily how much weight that is gained but rather the inability to lose the holiday weight, which has the potential to last a lifetime, and, thereby, have a serious deleterious effect on a person’s health due to the steady accumulation of weight holiday season after holiday season. Thus, although the total amount of weight gained over the holidays was relatively small (i.e., less than a pound on average), that amount of holiday weight gain gives a new meaning to the notion that a little means a lot, at least in terms of a person’s long term health and wellbeing.

Overweight and Obese At Greater Risk

The studies reviewed (including one with children) indicated that those who are overweight and obese are at special risk in gaining weight during the holidays. Compared to those of “normal” weight, overweight and obese study participants tended to gain as much as five pounds over the holiday season. In this instance, a lot really means a lot relative to the health and wellbeing of overweight and obese people in their battle to lose weight, a battle that is more often than not, lost.

Keep Your Body Moving

In the study by Yanovski et al., (2000), the study participants who were more active experienced the greatest weight loss, while those who were less active or hungrier gained the most weight over the holiday period. This suggests that people should not abandon their regular exercise routine or initiate one during the holidays. As Plato said over 2,000 years ago, “Lack of activity destroys the good condition of every human being, while movement and methodical physical exercise save it and preserve it” (Plato). Regular physical activity, whether in the form of a structured exercise program or just part of daily living routines, will help to keep your body energized and healthy during the holidays. Some of the short-term benefits of exercising and staying physically active during the holidays would include: More energy, a better sense of well-being, increased self-esteem and self-confidence, greater ability to cope with stress, healthier sleep and better able to fall asleep, burning of calories and weight management, along with better focus and concentration.

Eat Low-Energy Dense Foods

In the study by Yanovski et al., (2000), the study participants who were less hungry had the greatest amount of weight loss, while those who were more hungry gained the most weight over the holiday period. This finding suggests that creating a feeling of fullness or satiety would lead to less weight gain over the holidays. According to Rolls & Barnett (2002) and their nutritional theory of Volumetrics, the feeling of fullness people experience after eating is more a function of the amount or volume of food consumed than the number of calories or grams of fat, carbohydrate or protein consumed. Rather than the calorie content of what they are eating, it is the volume or amount of food that signals people to either continue or stop eating. Thus, eating low-energy dense foods during the holidays will help create a sense of fullness and, thereby, consuming less food.

Be Conscious of Calories

While experts may debate about how many pounds on average are gained during the holiday season, one thing is certain. Compared to other times of the year the amount of calories consumed during the winter holidays increases dramatically. Make no mistake about it, calories can add up unsuspectingly fast. All other factors contributing to weight gain were equal (e.g., type-quality of food, physical activity, stress levels, thyroid function, genetics, hormones, etc.), caloric intake is at the center of putting on unwanted, excess pounds, whether that be during the holiday season or any other time of year.

Whether or not you gain weight during the holidays distills down to one fundamental principle. That is, despite the nutritional, bio-chemical, physiologic, genetic or behavioral-psychological reason, if you consume more calories than your body uses, you will gain weight, no matter if those calories come from carbohydrates, fats or protein. It is a myth that only eating fat will make a person fat. At the end of the nutritional day, managing your weight during the holidays becomes balancing the number of calories you eat each day, with the number of calories you burn. For example, one pound of body fat is equivalent to 3500 calories. If you were interested in losing one pound of fat in a week, then you would have to burn 3500 calories more than what you typically consume in seven days.

Calories count. Hence, it is more nutritionally prudent to be mindful of how many calories you are consuming at any given meal during the holiday period, despite the touted advice of those who say counting calories is ineffective. Weight management is in large measure about counting the calories, especially during the holidays.

Keeping the above three recommendations (i.e., keep your body moving, eat low-energy dense foods and being conscious of calories) in mind over the holiday season will go a long way in helping not to receive that unwanted, unhealthy, un-returnable gift that keeps on giving.